Right to the Source: Exploring Science and History with the Library of Congress

Right to the Source: Exploring Science and History with the Library of Congress

Article excerpt

"Texting" in the 19th Century

Texting around the world may seem like a recent innovation, but real-time electronic communication between continents actually started more than a century and a half ago. On August 16, 1858, England's Queen Victoria and U.S. President James Buchanan exchanged messages in the first successful trans-Atlantic telegraph transmission--a vastly quicker mode than moving messages via ship. Carrying the electrical signal was a submerged cable stretching across the floor of the Atlantic Ocean.

Seven years later, mapmaker George Washington Bacon published The Atlantic Telegraph, a chart with maps, text, and diagrams (right) covering the history of telegraphy (from the Greek grapho, meaning "to write," and tele, meaning "afar"). That history, which began with "signal fires, torches, and trumpets," the chart explains, led to transmitting Samuel Morse's telegraphic alphabet via electric pulses sent through insulated cables underwater. Morse's short (dot) and long (dash) code is akin to the binary language of zeros and ones used in today's computing systems.

Bacon's chart shows the route of the trans-Atlantic telegraph cable and explains how it came to be. Describing the synergetic relationship between scientific ideas and engineering solutions that made transmission of electrical signals possible, the chart outlines scientific ideas about how telegraphs work using copper wire and magnets. Cross-sectional images of the cables flank the map and highlight the importance of conductors and insulators. …

A primary source is a work that is being studied, or that provides first-hand or direct evidence on a topic. Common types of primary sources include works of literature, historical documents, original philosophical writings, and religious texts.

A primary source is a work that is being studied, or that provides first-hand or direct evidence on a topic. Common types of primary sources include works of literature, historical documents, original philosophical writings, and religious texts.